Oxytocin (OT) functions as a neuromodulator in the central nervous system (CNS) to promote social behavior and affiliation in animals and. Because of its prosocial effects, researchers have begun to explore whether OT could be used as a novel pharmacotherapy to treat a variety of neuropsychiatric disorders characterized by social impairments, such as autism. Indeed, several studies have now emerged suggesting that intranasally administered (IN) OT can improve prosocial behavior in adults with high-functioning autism, including cooperation, reading facial expressions, and directing attention to the eye region in faces . However, the exact mechanisms by which IN-OT influence prosocial behavior in primates remain unclear, including whether OT acts centrally in the brain through the oxytocin receptor system (OXTR) or through peripheral feedback. Therefore, while OT is an extremely attractive potentials pharmacotherapy that could function to ameliorate social impairments and enhance prosocial behavior in humans, many questions remain about its mechanism of action and overall function. This is particularly true in nonhuman primates. Although they represent an ideal preclinical model for screening the behavioral and neurobiological effects of OT, only a handful of studies investigated the effect of OT on nonhuman primate social cognition. It is the goal of this study to compare the effect of IN-OT and intracerebroventricular (ICV) OT, and an OXTR-antagonist on tasks that address social perception social reward in rhesus monkeys. The tasks used are designed to mirror those used in studies of IN-OT in humans, and address some ofthe same social skills known to be impaired in autism, e.g., salience of social stimuli, social reward, recognition of familiar faces, and emotion categorization. Additionally, monkeys will be shown complex videos of familiar and unfamiliar monkeys engaged in social interactions during eye-tracking to determine how IN-OT affects the convergence of social attention. This project will provide seminal data on how OT affects social perception and social reward and contribute to it pharmacotherapeutic development.